The flow cytometry facility is composed of three flow cytometers and one full time operator. This facility has expanded since the last submission to include a FACScan and upgraded computers and software. The core is used by all investigators in the program project grant for both analysis and cell sorting. Off line analysis through the network interface allows for reanalysis of data, re-gating, additional subpopulation studies, etc. This core has been used heavily during the past granting period (hence the expansion supported by the Dean) and is involved in every aspect of the various projects.